


salt skin

by Trojie



Category: Supernatural
Genre: Accidental Voyeurism, Angst and Hurt/Comfort, Belts, Hurt Sam Winchester, M/M, Non-Sexual Kink, Painplay, Sibling Incest, Unhealthy Coping Mechanisms, non-sexual Sam/Cas
Language: English
Status: Completed
Published: 2018-01-15
Updated: 2018-01-15
Packaged: 2019-03-05 00:39:02
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 7,419
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13376436
Author URL: https://archiveofourown.org/users/Trojie/pseuds/Trojie
Summary: It's about permission. Or it's about pain. Or it's about something else entirely, Dean doesn't fucking know. All he knows is, he doesn't have enough trust left in him to just leave any part of Sam in Cas's care.





	salt skin

**Author's Note:**

  * For [sleepypercy](https://archiveofourown.org/users/sleepypercy/gifts).



It's the rhythm of it, more than the noise, that draws Dean in.

He's stripping all their guns, down to parts, rubbing them down and putting them back together again like he can't seem to do with anything else in his goddamn life, when there's a noise he doesn't recognise. Sudden, at first, but it settles in steady. It's a flat smack, something dull and worn, warm-sounding, echoing along the corridor over and over. Dean listens and picks out other sounds too. Sounds he knows and shouldn't, that he heard too many times in motel bedrooms and bathrooms not to recognise. Sounds being made by Sam.

They're dark and warm, starving - panic room noises. Craving noises. A couple years back down the line (or maybe more than a couple) Dean would have said they were sex noises, but Sam's been a damn monk since he got his soul back. Fuck, Dean would leave him to it and go bake a goddamn cake to celebrate if he thought Sam was honest to God getting laid - but he doesn't. He's not that naive. 

It's not that Dean doesn't trust Sam. It's that he doesn't trust anyone else. He doesn't trust the wards on this place. He doesn't trust the world not to pounce the second he takes his eyes off his brother. 

The distance between the armoury and Sam's bedroom isn't far. Dean picks up the gun he's just finished reassembling, and follows the trail as it gets louder and louder. 

Sam's bedroom door is closed. Locked. The noises are behind it. Dean wouldn't be much of a hunter if he couldn't open a locked door silently. 

The room's a mess of too bright antique light and beige and brick, and Dean's disoriented for a moment, no dark, no blood, no wrong to home in on. Against the opposite wall, though, Sam's a stretch of endless _sorry_ in the way he arches under Cas's belt, back naked and jeans hanging off his hipbones, and Dean's a microsecond from bursting across the room and shanking his best friend for taking a weapon to his brother (it's a weapon when you wield it, it's a weapon if you're a warrior) but then Sam's got that fine tremble to him that only comes when he's on the ragged edge, and just as Dean's about to move, Cas pauses and murmurs 'Yes or no, Sam?' 

and Sam moans _'Yes -'_

and Dean freezes. 

And the belt cracks down again, and again, and again, and Sam keeps saying yes, every time Cas asks and Cas does fucking ask, keeps asking until Sam chokes out _no, please, God, stop -_ and Cas does it immediately, drops the belt to the floor, and Sam folds inwards with a groan Dean knows that hasn't changed since their teens.

Looks like Dean should get to baking that cake, huh. His fingers clench into a fist around the grip of the knife in his pocket.

Cas just strokes Sam gently across his massive fucking shoulders, above the welts he made, until Sam stops shaking and moaning, and starts to straighten up. 

Dean doesn't run, but he backs away before he's caught.

Caught by Sam, that is. Dean knows for damn sure Cas knows he was there. 

***

He goes to bed, because he's got to do something, and lies there staring at the ceiling, hands clenched in fists next to him.  
He _gets_ mixing a little pain with your pleasure, he does - he can roll that way, for the right person, on the right night. And he understands the concept of having sex with people you trust, even if he doesn't believe in it himself - he'd rather risk VD and getting caught out by evil with his pants down than risk ruining what few relationships he actually has. But he can't work Sam and Cas out, because … because whatever the fuck he saw, that wasn't just fucking around. 

Goddamn it. Dean runs his hands through his hair; greasy, sweaty. He should wash. He feels gross, like he's been wrestling between these sheets, not just rolling. And nothing cools you off like ten minutes of icy water down your back. 

The walk down to the big, empty bathroom helps with cooling off, too. It's quarter past midnight, and Dean's footsteps echo. Regular, like Cas's belt slamming down on Sam's big, wide, carry-the-world shoulders. 

Dean makes a face in the dark, and it's half at himself. _It's not like you haven't seen this kinda shit before, Dean._ Hunters and pain - they're like cats and catnip. 

Dean's known a lot of hunters - too many - who got off on hurting people. Who just took it out on monsters instead of on civilians, got their jollies that way. And he's known a lot who got theirs from the other way around. For himself, he's more into the kind of sex that makes you smile, like ... with kissing, not biting. Touching, not hitting. Getting someone off, there's a rush in that he's never once got off killing. 

There's enough rough shit in his life. He's not into it in bed. But he gets it. If that's someone else's thing, he's not going to judge. He wonders, though. Does Cas leave Sam to it, after he's done whaling on him? Or does he clean him up? Does Sam, y'know, repay the favour? What does Cas even _want_ out of a hookup? How long has Sam been into this shit?

Truth be told, Dean thought neither of them was really into anything at all.

By the time Dean makes it to the showers he's half-hard in his pyjamas. He shoves his way through the door all ready to turn the damn thing to frigid cold and maybe give himself something else to fucking think about, but when he gets in there, it's not empty. It's all steam and heat, and before Dean can announce his presence, Sam ducks under the spray (of the shower closest to the door, of course) with his eyes closed, rinsing the shampoo out of his hair, and gives Dean the full-length voyeuristic peep-show pose. 

Dean should say something. He should at least cough loudly. He's going to make a noise, say hi or something, he is - but the sight of Sam turning makes him stop. It's like a goddamn oil-painting in red and purple. Streams of foam run down Sam's shoulders, while he cards his hands through his hair, but when the water runs clear, there's _layers_ of bruise there, and welts. 

Sam's body has been taking a lot of punishment, it's written out there on his skin for Dean to see, a clear view, no Cas and his shadow to block the details. It's not all from tonight - this has been going on a while. That's weeks' worth, maybe - months. God knows how long - bruises fade eventually, no matter how hard you hit. Cas has been beating Sam black and blue and Dean hasn't even seen it. Hasn't noticed, while something like this has been going on underneath his fucking nose.

Sam stretches, under the water, and something pops. He groans, and drags a hand down to massage at his own shoulder. Dean wants to go over there and help - he kneaded the growing pains out of Sam when he was a teenager, he knows he could do something about this ache too. The urge to step under that water and take care of his brother is hard to squash. 

Dean watches Sam half-turn, run his hands down his torso to his - whoa, okay, that's … that's Dean's cue to leave. He's got to, he has to, this is - this is crossing a line. He's more than half hard now, he's damn near all the way, his dick is so heavy it aches, tents out the soft cotton of his pyjama pants, and fuck, but he wants to just press the heel of his hand against it, just for a second. 

No. 

He just can't. Can't put a hand on himself thinking about Sam like this, all hurt and aching, not if he wants to be able to look himself in the eye in the mirror tomorrow. And yeah, okay, he shouldn't be putting a hand on himself thinking about Sam at all, and still be able to look himself in the eye in the mirror, but that ship sailed a long, long fucking time ago.

But there's a difference between thinking and perving. He's got to leave.

He's going to leave, he's about to move, when Sam, one hand on his dick, water pouring down his body, opens his eyes and looks straight at him. 

'I'll just … come back later,' says Dean, traitor feet suddenly working again. He starts backing away. 

'Dean -' Sam calls from behind him, but there's no fucking way Dean's turning around. He's hard as iron in his pants, cold and guilty in his chest. Maybe Sam follows him, but Dean doesn't stop to let him catch up.

***

The next morning, Dean corners Cas in the archives when Sam's out on a supply run. 

'I know you and Sam are messing around,' Dean growls into Cas's face, no preamble, no warm-up. 'Fucking. Whatever. And okay, you're both adults, I can't stop you. But I can tell you one thing, Cas. If you hurt him, I will kill you. I swear, I will _kill_ you.'

Part of him means it, too. Dean … Dean's never been prepared to dig into the reasons he gets antsy when Sam has girlfriends, but he knows he does. Other sets of hands on Sam's body he can deal with - doctors or women or, hell, even monsters, he can rationalise as things that happen, and if they go wrong, he'll deal with it. Other people in Sam's life … have historically not gone so well. 

Even Cas. A one-off, sharing-foxholes thing Dean could maybe turn a blind eye to, but not this.

'I think you've missed the point of why we 'mess around',' Cas says calmly, putting little quote marks around Dean's words and neutralising them. 'But we're not fucking.'

'I know you get all freaky-deaky in the sack,' Dean snaps, feeling something tighten in his gut just thinking about it. 'I don't need the details. And I also know Sam could kick your ass almost as hard as I could if he didn't want it, and vice versa. I don't mean hurt like that, Cas. I mean -'

'You mean emotionally,' Cas supplies. 'I promise you, Dean, that is the last thing I will do. I am trying to help Sam. I would never hurt him.'

'Yeah, well,' says Dean, hackles still up but it's like punching smoke, Cas isn't giving him the fight he's been spoiling for. So he changes tack. 'You better not. And while we're at it, you wanna maybe stop beating him half to death?'

'It's what he asks me for,' Cas says, as if that makes it okay. Then he says, 'if you're worried, you could supervise,' kinda offhandedly, and Dean gapes at him.

'Excuse me? You want me to what?'

Cas shrugs. 'It might help you feel better about this if you see what we do.'

'No, Cas,' says Dean harshly, ignoring his treacherous dick twitching. 'Just. No. Jesus. I'm not watching you have kinky sex with my brother. That's just wrong '

'You've watched him have sex frequently,' Cas says. 'He's watched you.'

'We have _not_ ,' Dean growls. 'We just -'

'You were present. You were in earshot, or close enough to act if something went wrong. You listened out for him, or he sat outside in the car and watched through the curtains. It's alright, Dean. I'm not judging -'

'Oh, how very goddamn generous of you,' Dean snarls. 'Well, I am judging. I've seen him, Cas. He's all over fucking welts. That is not okay. Find something else to get off on, or I swear to God, I am nipping this little sexcapade in the bud.'

Cas blinks. 'I'm not actually having sex with your brother. And, with respect Dean, it isn't you I'm beating. This isn't yours to stop.'

***

Two more days, and Dean's sleep is shot to hell even more than it usually is, and every time he even thinks about putting his hand to his dick it's Sam in the shower that comes to mind and that just … something bugs him about it. More than the usual, anyway. Tonight's no different. Dean pulls his hand out of his jeans, rolls over, buries his face in the pillow and tries to think.

It's not the pain. Sam can take pain. Sam _needs_ pain, sometimes - Dean stopped worrying about that years ago. Adrenalin and endorphins are nothing compared to demon's blood, and anyway. Cats. Catnip. Sam's not the first hunter to come by that little quirk. 

The pain thing bothers the shit out of _Dean_ , that's true, he hates it, hates the idea that Sam's hurting, but that's not what's gnawing at him so bad. 

The yes or no thing, maybe - there's something about that Dean can't put his finger on. But, well, Dean feels like shit thinking about it, but it's that it's Cas. Specifically Cas. It's the angel thing. Sam and an angel. There's something in that. Something … something Dean should maybe be worried about. 

He can't sleep, not knowing Sam's down the hallway doing God knows what, getting God knows how fucked up. Dean trusts Cas but he doesn't trust him that much, and fuck knows he doesn't trust Sam with himself.

Dean's pulling his shirt back on over his head before he even knows he's made the decision. He's still doing up his belt buckle when he knocks on Sam's door.

Cas answers. 'I wondered how long you'd wait.'

***

Dean ends up sitting on Sam's bed, watching Cas handcuff Sam's hands behind his naked back. 

'If you have any questions, ask,' Cas says calmly, as the last lock clicks. 

Sam's tense, Dean can see it in the curve of his back, trying to cringe away from being seen, like he can hide, like he's not taking up most of the space in this tiny room. Dean doesn't say anything. Cas eyes him for a moment, but then sighs, shrugs, and pulls his belt free of his trousers. He runs a hand softly over Sam's shoulder, and Sam only tenses up more. Dean doesn't like this.

The first smack of leather on skin, though, and Sam's muscles unknot like ropes, and he leans into the wall like it's holding him up, taking his weight on his left shoulder and turning his face to the side, cheek pillowed on the bricks. His eyes close, his breath evens, and Dean hasn't seen him look this peaceful in ten fucking years, not even when he's asleep. 

Dean's own heartrate is an ugly, out of sync whine, like he's only firing on five cylinders. 

'How many, Sam?' Cas asks, pausing with his arm up high. 'How many tonight?'

'Thirty,' Sam breathes out. Jesus. Dean's been whipped, for sexy and not-sexy reasons. Thirty with a leather belt seems like a lot to start off with.

'Count them for me,' Cas tells Sam, and starts in, bringing the belt down with a sharp crack, over and over. Sam bites out a number every time.

Cas gets to five before Sam's sobbing. 'Do you want me to keep going? Yes or no?'

Sam writhes. The red stripes over his back look hot and painful but he's squirming back towards Cas and the belt, not away. 'Yes,' he moans. 'God, yes. More.'

'Keep counting, then,' Cas tells him, and raises the belt again.

By the time Cas gets to ten, Dean can see that Sam's hard in his jeans, and he's straining backwards, shoving his ass out, face still to the wall, begging with his body so hard Dean can practically hear the words. 

By nineteen, Sam's legs are spread so wanton far-apart and his back is arching so hard that Dean doesn't understand why Cas isn't stepping in between them. That's not a suggestion, it's a goddamn handwritten invitation card with gold embossing. Dean knows sex, and he knows how to read his brother, even like this. But Cas stays an arm's reach away, and the welts on Sam's skin are all he gets. He's still counting. 

By twenty nine, the jeans are dark with sweat at the waistband, Sam's throat is working with sounds he won't let out, and it's making Dean squirm, seeing his brother _need_ so hard something that Dean categorically cannot, can never, give him. He wants to shake Cas. Cas just keeps on bringing his arm down, making the belt crack. 

'One more,' Cas says, pausing. 'Do you want it?'

'...no,' Sam whispers, and the beat where the strike should have come falls empty instead. Sam sobs, and Dean watches the orgasm shiver down his spine, every muscle catching and releasing in sequence. Cas grabs Sam as he sags, before he can drop, murmuring to him words Dean only half-catches, and pulling him to the bed. Sam pours onto it like he's made of jello, feet hanging over the edge like they always do when he's too wrecked to pull his knees in. Dean reaches over on autopilot and tugs at them, forcing Sam to crook up so he'll fit. Sam half curls towards him. 

Dean can't resist running his hand through Sam's sweaty hair, stroking it off his face. 'Heya, Sammy,' he murmurs. 

'Dean,' Sam says back, swallowing the vowels so it's more like a hum than a name.

'Y'need anything?' Cas has gone to get water, and whatever else it is they usually need post- whatever this is, but Dean has to ask. 'Anything at all.'

Cas comes back into the room with a glass of water, and a washcloth. Sam winces as he rolls onto his back and, with some effort, sits up. He looks okay, Dean realises. Sore in the way he moves, sure, but easier in his skin. The haunted look in his eyes has receded again. 'A little privacy?' Sam suggests quietly, fingers toying with the button on his jeans, and Dean realises what the washcloth is for. 

'Right,' he says. 'Right, yeah, I'll just -'

Cas meets Dean's eyes as he leaves, and raises one eyebrow in a question. Thing is, Dean doesn't know what he's asking.

***

Sam's out on another supply run. This time it's Cas that corners Dean, in the kitchen while Dean's trying to work out if he can throw something hot to eat together in time for Sam to get back, to use up the shit they do have, or if he should just wait until he gets some fresh ingredients and can make something a bit more, y'know, interesting than tomato soup. 

'Do you understand now?' Cas says from behind him. Dean's been hunting too long to startle properly when he's surprised, but he does blink. Cas moves like a fucking ghost when he wants to.

Dean shrugs. 'He gets off on punishment,' he says. 'What's to understand?' It's a good answer. Pat. Easy. And mostly true.

'Dean -'

Of course the fact that it's never that easy, that there's something going on in Sam's head over this, this whole pain/permission mess that Dean can't get a read on no matter how hard he tries, that's beside the point. Dean's gonna bury this one six feet deep, where the fact that there's nothing for him to do here that won't make his brother hate him can be hidden with all the rest of it.

'It's really not that complicated, Cas,' Dean says, liar, liar, liar, best liar in the world. 'Everyone's got a hot button. I appreciate the whole trying to make sure I'm okay with it thing, but I don't really need to watch my baby brother get his rocks off again.'

Correction: Dean's not sure he _can_ watch that, watch Sam need so hard, and not do anything … unbrotherly.

Cas just looks at him, solid and steadfast. 'I was hoping you could help _me_ understand,' he says, and, wait, what? 'I can give him what he asks for, but I can't … I can't read him like you can. I don't know what he wants, that he isn't saying.' He makes a wry face, mouth tightening for a split second. 'What I do to him, it helps, but it isn't enough, and he won't tell me anything else. You know Sam better than anyone. Please - help me help him.'

_No no no no no,_ Dean's brain is screaming at him, _no no no, we don't talk about this. We're not going to talk about this._ But. '… I'm gonna need a beer.' He pushes Cas into a seat at the kitchen table and goes to the fridge. 'You want one?'

'Sure.' But Dean can tell by the face he pulls when he takes his first sip that he hasn't got a taste for it yet. Dean drinks his down, trying to work out what to say. What the hell there is _to_ say. He doesn't have fucking words.

Cas starts, though. 'I'm missing something, aren't I?'

'Why d'you say that?' Dean's hedging, knows he's hedging, but god fucking dammit he doesn't wanna talk about what he saw in there. The way Sam's eyes cleared. The way he relaxed into every fucking stroke. The way he asked for it.

'Because I've been approaching this as something to help Sam's psyche recover from possession, but your immediate focus has been on the sexual aspect.'

'Well, c'mon Cas, you can't tell me you haven't noticed that he gets off on it,' Dean points out. 

'On what, though?' Cas asks. Before Dean can butt in, he keeps going. 'What about what I'm doing is it that he likes?'

Dean kinda gets the feeling that Cas doesn't quite understand getting off at all, except the physical part. Dean … Dean really doesn't wanna have to explain it, either. 'I dunno,' he says. 

Cas takes another swig out of his beer and makes another face that would have had Dean smirking on any other day. 'Then I guess we're at an impasse,' he says, putting the bottle down. He looks like a kicked puppy.

Dean tips his head back for another swallow, and tries to think. Silence reigns in the bunker kitchen, as Dean's embarrassment slowly cools and the reality of the situation kicks in. Sam needs help, Dean knows it. And Cas is helping ... but it's not enough. 

Not quite, and Dean knows why.

'You know he wants to get fucked, right?' he says after a while, staring at the label bits he's torn off the beer bottle because that means he doesn't have to look at Cas. 'I mean. You're not doing anything wrong, as far as I can tell, you're just ...' Not giving him enough, Dean doesn't say. God, he doesn't even want to think about the kind of fucking Sam's craving, if his idea of foreplay is thirty lashes with a leather belt.

(Except, at night and in the shower and far too fucking often outside both those places, he is thinking about it.)

'He's never asked for it,' Cas says. 'And the entire purpose of the exercise is that I only do what Sam asks for.'

'He wants it,' Dean shrugs. 'Trust me.'

'I do,' Cas says, sincerely enough that it makes Dean suddenly, itchily uncomfortable. 'And so does Sam.'

'Well that's beautiful, Cas, thanks,' Dean says brightly. He drains the rest of his beer. 'I'm gonna go upstairs and write it down in my journal in a pink glittery pen.'

Cas's expression as Dean walks away is definitely one he learnt off Sam.

***

When Cas and Sam disappear the next evening, Dean goes to the firing range instead of following, finding out if they're going wherever together.

One by one, he puts his weapons through their paces. Puts himself through his paces. Because silver ammo doesn't have the penetration of lead, so you gotta correct for that - because a shotgun kicks differently to a pistol, because you can't throw a knife the same as a dart, because there are so many fucking special circumstances and frankly, after Hell, Dean let himself go a little on the fine detail. There were some things he didn't want to practice any more. 

The heft of his 1911 in his hands though, that's still perfect. It's like a pearl and steel extension of his goddamn body, carried so close for so long, in the hollow of his back tucked under his waistband, or under his pillow, that he almost doesn't know what it feels like cold. And it's natural to squeeze the trigger between his breaths, to see six holes cluster in the target in front of him, dead centre. 

'We gotta start taking you to funfairs,' Sam says behind him, after he's lowered the weapon. 'We'd make a fortune in stuffed animals.' 

So they're not at it tonight, after all. 'What do you want, Sammy?' Dean asks, sliding the gun back into his waistband. 

'For you to stop avoiding me.'

'I'm not avoiding you.' 

'Yeah, Dean, you are. And I'm sorry, okay, I'm sorry that Cas's little demonstration weirded you out, or whatever, but we need to get past that so that we can work like a team again. Properly.'

'Why don't you just tell Cas you want him to fuck you?' The question slips out before Dean can rein it in, and he winces, but he holds Sam's gaze. 

Sam stares at him. 'I don't.'

'Yeah you do, Sammy.' Dean shrugs. 'You think you're hiding it?'

'I don't want him to fuck me,' Sam says in as dignified a tone as he can apparently muster. Dean just raises an eyebrow, because seriously? Sam breaks off the high and mighty act and glares. That's the Sam Dean knows. 'I don't want him to fuck me, Dean, because he doesn't want to do it.'

Dean goes to argue and then stops. 'Excuse me?'

'Did I stutter?'

Dean tries to joke it away. 'Dude, we gotta work on your self esteem.'

'It's nothing to do with me.' Sam crosses his arms over his chest defensively. 'He's a multidimensional celestial being, Dean, he's not interested in me that way. Or in anyone, I'm pretty sure.'

'Explain Meg, then. And that freaky Reaper chick. And, oh hey, that one time he had a goddamn _wife_.' 

Sam looks like he'd like to throw his hands up in frustration, but he keeps himself clamped tight down, only the way his jaw tightens giving him away. 'Experimentation?' he says. 'And you can't tell me you've never been in a situation where you just … did what you thought the other person wanted because you liked them, and you didn't know any better,' he adds, and maybe Cas has been talking, because Sam's squirming like he knows things but shouldn't say them. The idea that maybe Cas has confided personal things to Sam rather than to Dean feels weird. Off. As off as the idea that there are things about Sam that Dean doesn't have access to. Makes him feel surplus. 

'Alright, say he doesn't want to fuck you,' Dean tries. 'You still want to get fucked.'

'I can't believe we are actually having this conversation.'

'That's not a no, Sammy.'

Sam shakes his head, exasperated. 'Okay, fine. Yeah, I wanna get fucked. And when I was eight I wanted a pony. It doesn't matter. What matters is that Cas is helping me out with some stuff here, okay, and I need you to get your head out of your ass about it, because this is the best I've felt in years, and we still have work to do.' 

That, okay, that is true. And it stings Dean that Sam's the one saying it to _him_ , because he's been Mister The-Job-Comes-First for twenty goddamn years or longer. 

'And what are we gonna do when you can't work because you let Cas beat you half to death, huh Sammy?' Dean snaps, overly defensive. 'Congratulations on your sexual liberation and everything, but did you think about that?'

Sam does actually throw his hands up this time, like he could beat the air bloody out of anger. 'I knew you'd get it wrong,' he growls. 'I knew - I told Cas you'd miss the entire fucking point.'

'What point?' Dean says. He gets in Sam's face, shoves him, because he clearly wants a fight, so Dean'll give him one. He can give him that at least. 'You're an adrenaline junkie, Sam. Admit it. C'mon.' He takes a swing. Sam ducks. 'I shoulda seen it before, you've always been scrappy. Feel that? Blood pumping through your veins now, huh?'

Sam sidesteps, whip-fast. He's fucking huge now but he hasn't lost the reflexes. He was always faster than Dean.

But Dean's old tricks hold true too - he turns the momentum around and Sam isn't fast enough to duck this one as well. Dean's fist catches him across his high, sharp cheekbone. 'You sure?' Dean asks. 'Isn't this what you were begging Cas for? Bruises?' Dean can see it now, the sweet, hot satisfaction in Sam's eyes after he'd come his brains out with Cas's marks on his skin. 'Is this what you want, Sammy?'

But Sam's eyes are huge and hurt, really hurt, above the redness from the punch, when Dean looks up at him. 

'No, Dean.' His voice is shaking 'Of course it's fucking not.'

***

'Do you have any practical advice for having penetrative sex with a man?' Cas asks Dean three mornings later. Dean swallows hot coffee too fast and kinda can't answer him for a solid minute. Which is good, really, because it gives him a minute to fucking process that. 'I understand the basic process,' Cas continues, 'but I've never tried it, so I thought it would be best to ask. You have a lot of sexual experience.'

'With women,' Dean points out, still coughing. 

Cas squints at him. 'Exclusively?'

'Well … no, but …'

'I tried using Google but most of the instructional videos were very difficult to make sense of.'

Dean puts his hand across his eyes, praying to anything out there to give him strength. 'You're not going to get good instructions off porn, buddy,' he says. 

'Well, how does anyone ever learn?' Cas grumbles. 'Your species is so secretive about sex, and yet you expect everyone who has it to be good at it, and there's no clear learning process whatsoever.'

Dean eyes Cas, who looks annoyed, but just the usual kind of annoyed. 'Cas,' he says, a little carefully. 'Is this about Sam?'

Sam hasn't said one word to Dean since their fight in the armoury. Dean hasn't said anything either. He made coffee as a peace offering yesterday. Sam left it to go cold.

'You seemed to think it would help him,' Cas says. He sighs.

'I said he wanted it,' Dean hedges, because okay, yeah, but then again maybe adding actual sex to the mix will just fuck things up in a new, different direction. Him sticking his nose in hasn't gone so well so far. 'I didn't say it would help.'

Cas regards him solemnly for a moment. 'Sam doesn't get the things he wants very frequently,' he says. 'Neither of you do. And many things have been done to him, or for him, without his opinion coming into it. What I'm trying to achieve is to give Sam some sense that his choices will be listened to. That he can have the things he wants.'

'He won't want it if you don't want it,' Dean points out. 'If he hasn't asked for it, he's probably got reasons.'

'I want to help him.'

'But do you want to fuck him?' Dean's life, this past week, has involved so many goddamn conversations he didn't want to have. But he's been thinking about what Sam said, about what Sam _wants_ , and he thinks he might have a handle on it now. Too little, too late, maybe, but whatever. He grits his teeth and keeps going. 'Because I'm telling you, if you don't want _him_ , he won't want you to do it.'

Cas drops his head into his hands and makes a frustrated noise. 'Humans are ridiculous,' he says. 'It's a physical, supposedly pleasurable, act. I've done similar things before and not found them particularly unpleasant, and I have absolutely no objection to doing them again for Sam, if that's what he wants. I flog him with my _belt_ ; why is it the sexual intercourse that the pair of you shy away from?'

Dean looks at him and sighs. At the very least, he doesn't want Cas trying out whatever the fuck he learned from googling gay porn on Sam. 'Yeah, well,' he says, because he doesn't have an answer to that. 'Okay, look. You at least know what a condom is, right?'

And that's how Dean ends up explaining the mechanics of how to fuck dudes to an angel of the Lord, with the aid of anatomical diagrams drawn on cocktail napkins. His life is actually the worst.

***

Sam basically ambushes Dean in the armoury the next evening. Well. Night. Morning. It's like 3am, okay, and Sam's in his goddamn pyjamas. Dean just didn't bother going to bed. 'Did you put him up to this?' he demands. 

'Put who up to what?' Dean retorts distractedly, tapping salt shells to settle their contents. 'Nice to see you too, Sammy, it's been a while.'

'Cas, and you know damn well what.'

Dean has had just about enough of this. 'Y'know what, how about the two of you talk to _each other_ about this fucked up little therapy kick you got going on, instead of making it my problem?' he snaps. 'He asked me for pointers, Sam. He came to me asking how to fuck you, to give you what you need, and God help me but he's a determined son of a bitch. So yeah, I gave him the talk. Just like I gave you the talk when _you_ asked me how to fuck someone. What was I gonna do? He was trynna take notes off goddamn porn. Forgive me for saving you from _that_ experience.'

'I never asked him to fuck me. And funny, how he never got that idea until you came along, isn't it. Sex isn't the be-all and end-all of two people interacting, Dean.'

'I never said it was. But he asked me what he wasn't getting right, so … what else was I supposed to do? Sorry, man. And I'm sorry about the other night, too. I shouldn't have … whatever.' He takes a harsh breath through his nose. 'But it's pretty obvious. It gets you off, him hitting you, it gets you off even without a hand on you, but you _want_ a hand on you. You want more than that.' Dean sighs. 'I dunno why you're turning him down, Sam. It's Cas. He wouldn't offer if he didn't think he could do it. He'll - he'll be good to you.'

Sam looks away, and the barest shadow of a blush crawls up his throat. He knows Dean isn't wrong. Dean feels something bitter, something that tastes like loss, in the back of his throat. He picks up another shell and turns back to his work, figuring Sam'll go. Maybe he'll find Cas. Maybe they'll fuck tonight, or this morning or whatever, in Sam's room behind a locked door. Dean will stay here. It's been awhile since he pulled a good old fashioned all-nighter. Their ammo stocks are getting low, so it's not like he's wasting the time.

But Sam doesn't leave. He just … looms. Dean packs two more casings, pointedly, but Sam doesn't budge. 

'What, Sam? Either say whatever it is you're spoiling to say, or go.'

Sam crosses his arms. 'I'm just trying to figure you out. Because it sounds like your suggestion is to get pity-fucked by someone who doesn't physically want me, and has to do research to figure out how.'

'What do you want me to say, Sammy? Talk to him about it, for God's sake. I dunno! Find someone else to fuck you, if he really doesn't want to or you don't want him to, or whatever the hell it is that's stopping the pair of you.'

'Who?' Sam demands. He's pacing, or he would be if his legs weren't so damn long - this room is basically two strides for him, up and down and up again. 'Exactly who, Dean, can I get to … you know what, this is ridiculous.'

Dean gets up and grabs him by the shoulder, sick of the melodrama. 'Seriously? Go to any bar you like, unclench for five seconds, maybe smile at someone, God forbid, and you'd find someone who'd fuck you. In a heartbeat. Look in a _fucking mirror_ , Sam, Jesus.'

'That's not what I - no, Dean, I'm not gonna go pick up a stranger. Maybe that's your coping mechanism, but it sure as hell isn't mine.'

He tries to pull away but Dean just clamps his fingers tighter. 'Picking up strangers has always worked for me.'

'I'm not bringing a random civilian back to the bunker, Dean! And I'm not … not gonna -' He drags his hands through his hair, tugging at it frustratedly. 'I have nightmares, Dean. I … I scream, and I lash out, and I see things … it's not safe. I can't explain that to a stranger, and I can't ask them to -'

Dean's fingers tighten again, involuntarily, and he hugs Sam to him almost just so that he doesn't have to see the defeat in his brother's eyes. Sam pulls himself back though, clearly trying to keep his control, and isn't that just Sam through and through?

'So can you - can you leave it, please? If Cas asks again. Because I don't … want that … so bad that I'll risk what I do have,' he finishes lamely.

Dean's so tired of not being able to help him, he's _so tired_ of it. 

'I'll do it,' he says. 'Sam. I said I'll do it.' He licks his lips, suddenly dry-mouthed and terrified. 'You gotta let me help you, man.'

***

Dean draws two lines. Line one is condoms. They bleed and get bled on enough, and Dean's got enough of a chequered sexual past - hell, Sam's been around the block a few times too, even if not for a while- for that to be a no brainer. 

Line two is pain. He can see what the pain is doing for Sam, and he's not arrogant enough to think that his dick is magic and that he can fuck away Sam's problems, but Dean will not beat his brother. After everything he's done, Dean just … he can't. 

He won't. 

But Cas will. 

'How many tonight?' Cas asks gently but firmly. Sam's blushing and squirming, and Dean thinks he's gonna pull the plug rather than commit to anything, but Cas just keeps eyeballing him, and eventually Sam bites his lip and says, 'I dunno. Just … keep going til I say?'

Jesus Christ. 'Sam -'

'Then take off your shirt,' says Cas, overriding Dean's protest. When Sam isn't looking, Cas glares at Dean. Right. This is Sam's gig. Dean subsides. 

He doesn't know what to do, if he should sit, if he should stand, if he should … do anything? He perches on the edge of Sam's bed and waits. Cas pulls his belt out of his belt loops, takes Sam's shirt from his drooping fingers and tosses it aside.

'Are you ready?'

_No_ , thinks Dean, but Sam says 'Yes,' already rough.

'Good,' says Cas. 'I need to you get on the bed, then. Both of you.'

Dean's brain shorts out about halfway through Cas's choreography. He ends up flat on his back on Sam's terrible granite mattress, and Sam's on all fours over him, and won't meet his eyes. It's like the worst kind of awkward missionary position married people sex Dean can imagine. Right up until the crack of Cas's belt in empty air sounds, and Sam looks down at Dean in shock. Like this, with no wall or curtain of Sasquatch hair in the way, Dean can see Sam's expression and it is _raw_ \- for two seconds, before Cas cracks his makeshift whip again and Sam's eyes clench shut.

'Easy,' Dean murmurs, curling his fingers around Sam's ribs, low enough that they won't get caught by Cas's belt. 'Hey, hey, look at me, c'mon. Sammy, it's okay. I'm right here.'

Sam doesn't open his eyes. 

'Yes or no, Sam?' Cas murmurs, somewhere above them. 

'Yes,' Sam says shakily. Cas's belt slices into him, and the crack of leather on skin breaks that glass-like moment. Sam _relaxes._ Breathes, properly for once, a long slow exhale while Cas's arm pulls back, and when his eyes open they're … serene. 

'Again?' Cas asks. 

'Yes,' Sam says, almost a moan. Dean's heard Sam make every damn noise under the sun, and that one … he wants to be the one to make Sam make that noise over and over and over until his voice is gone. Dean slides his hand all the way down all the miles of Sammy-spine and stops at the waistband of Sam's jeans, fingers twitching. 

'And this,' he asks, has to clear his throat just a little to get the words out. He flirts a finger under the sweaty denim. 'Sam? Do you want this?'

Sam shifts, pushing up on his hands enough to look Dean in the eye. 'No.' 

Dean's heart goddamn stops. Okay. He can … that's okay. He goes to pull his hand away, but Sam shakes his head. 'Leave it there,' he says. Cas has paused, and he meets Dean's eyes as Dean bites his lip. Dean knows that if he does what Sam says, leaves his hand splayed there on the small of Sam's back, then he's trusting Cas not to hit him. 

They're both watching him. 

'Okay,' Dean says softly.

'Do you want another, Sam?' Cas asks, after a beat. 

Sam puts his head back down onto Dean's shoulder. 'Yes.'

The belt hisses down again - Dean feels the air shift over the back of his hand, and it raises goosebumps, must have come close, very close, and Sam's wince says it was a hard one. Dean keeps his hand steady, twitches his fingers trying to pet his brother, soothe him through the strike, without moving. 

'More?' Cas asks. 

'Keep going,' Sam says. His mouth is soft and wet against Dean's collarbone. 'Keep going til I say stop.'

Dean bites his lip hard, but doesn't say a word, just keeps circling the pads of his fingers, tiny, tiny movements as much as he can risk. He keeps his pinkie above the waistband and stays there. Sam's breathing hot and hard against him and his body unknots with every yes, dips lower with every hit, until they're God knows how many strokes into it and Sam's hips are flush with Dean's. Dean strokes his sweaty skin, cards the fingers of his other hand through Sam's hair. Sam's hips are working a good rhythm, a settled-in, ride-you-all-night pace, in time with Cas's arm coming down. 

Dean's zipper is hurting him, digging in, jammed between how hard he is and how hard Sam's pressed against him. He _wants_ , but Sam hasn't said yes. And Cas is still working him over. 

Even when he's fucking whimpering, sobbing with every breath, and Dean can feel the heat radiating off the places Cas has hit, so close to his hand, Sam still doesn't say stop. Even Cas is starting to look concerned, when their eyes meet. Dean desperately wants to tell him to ease it off, because this is a lot of punishment, but.

Instead he twists til he can kiss Sam's forehead, and forces himself to say, 'You still want more, Sammy?'

He's expecting a yes, he's ready to force himself to be okay with it, but it doesn't come.

'No.' Sam's voice cracks. 'Stop.'

Cas, arm halfway back up, has too much momentum to just stop - he jerks hard, and the belt makes enough of an arc to come around and snap him on the shoulder. He barely even flinches, face full of concern. 

Sam's twitching under Dean's hands. Slowly, Dean moves his hand until he can touch the edge of Sam's waistband again. It's soaked, sticky-damp with sweat. 

'Do you want more, Sam?' Dean asks slowly. 'Do you want this?'

Sam shivers. 'Yes.'


End file.
